Discover the secrets to a thriving garden by understanding what your plants really need. From soil testing to choosing the right fertilizer and nutrients, learn how to nourish your garden like a pro and watch your plants flourish beyond your expectations.
From Sarah’s garden to yours
Like all living things, plants need nutrition to stay happy and healthy. We tend to like a wide variety of things to eat with complex combinations of ingredients making up our favourite meals. Plants, on the other hand, have a simple diet and understanding how to support them as they grow will result in a beautiful and productive garden.
Let’s have a look at what needs to be considered when preparing our gardens for the growing season.
Check your soil
It can be handy to do a soil check, even if you have gardened for many seasons. The balance of soil is constantly changing and the actions of the gardener often involve taking away plant material that contains nutrients you have previously added to the soil.
Before adding anything to the soil, find out what state it is in to avoid unnecessary additions. Sending soil away for testing can give you a comprehensive analysis, often with guidance on how to improve it. A soil test kit from the garden centre gives a basic DIY understanding of the balance in your soil.
Alternatively, sowing a small patch with a fast-growing crop like mustard will give you an indication of the state of your soil. Does it germinate easily? Is the growth fast or slow? Are the leaves large or small? A healthy soil will give results to please Goldilocks – not too fast, not too slow; not too big and not too small, and so on.
Leaves should be a healthy shade of green; pale yellow leaves can indicate a soil problem. Plants have a way of telling us through their leaves if they are missing vital elements. A quick search online for nutrient deficiency in plants will present easy-to-understand charts to interpret what you are seeing.
Know what you are growing
Just as people like to eat different things, plants have preferences that can determine the outcome of your crop and the beauty of your flowers. A leafy plant grown for its foliage such as lettuce, cabbage or hostas appreciate more nitrogen than a plant where the treasure lies in the fruit or flower. Too much nitrogen and the latter will forego the desired blooms and fruit for luscious leaf growth. Taking time to find out what your plant needs and how to care for it will always result in a more successful outcome.
Loving the soil
It is easiest to prepare the soil well before planting, this gives plenty of time for the micro communities to get to work on breaking down the soil additives so that the plants can hit the ground running.
There are a myriad of lotions and potions available to the gardener. They come in various forms and originate from animals, plants or a mix of the two. All will ultimately suit the needs of the plant but it is interesting to note that there are some fertilisers that match the values of the gardener also such as organic and even vegan options.
Carefully curated synthetic fertilisers with known compositions have their place, and organically sourced additions add more value than just food to the soil and its communities, it is handy to know though that the plants don’t really care where their nutrients come from and once it is in an elemental form it doesn’t matter.
You can’t go wrong with compost, which is effectively a replica of the accumulated leaf litter and plant material that falls to the forest floor. It is beneficial for soil structure and has the ability to absorb moisture. It can lessen the impact of a clay or sandy soil, and is valuable to the micro communities as they go about their business. It is more of a soil conditioner than a fertiliser as it has low fertility. Take note that it is possible to have too much of a good thing and you generally don’t need more than a 5 cm layer each year for optimal benefit.
Manure is another beneficial addition, but it is essential it is well rotted with a soil like texture and no longer smelling of manure. If it is too fresh, it can burn roots which will interfere with their ability to absorb nutrients.
The key factor is not to overdo it. Knowing the state of your soil, and what your plants need means that you only need to add what is missing. Too much can cause unbalanced growth making plants more susceptible to pests and disease. It can also be wasteful as the excess is washed away. It can even cause chemical interactions deep in the soil that interfere with the ability for other abundant nutrients to be absorbed.
Always follow the instructions on the packet or bottle and err on the side of caution. A spreader is a a great way to apply nutrients to give even coverage. It is easier to add a little more later than undo an over fertilised garden.
A well-prepared soil can, in some cases, last an entire growing season. Having said that, some plants are known as gross feeders, which means they are exceptionally hungry and will need nutrient top ups during the growing season. A regular liquid feed can be a quick fix, or the addition of a slow-release fertiliser, gently scratched into the soil above the root zone several times during the growing season can give the plants the boost they need.
What do plants actually need?
Plants only need 16 elements in their diet, 19 if you include Carbon, Oxygen and Hydrogen that they pull out of the atmosphere. The bulk of their diet is made up of Nitrogen (N) which is mostly used for the luscious green growth; Phosphorus (P) is responsible for ensuring the flowers, fruit and roots get the support they need to develop and flourish. And finally, Potassium (K) which helps build strength, vitality, and health. If plants were to have a food pyramid these would be at the bottom and consumed in abundance.
There are other nutrients that also have a vital role in the inner workings of the plant including Calcium, (Ca) Magnesium, (Mg) and Sulphur (S). The trace elements - Boron (B), Iron (Fe), Manganese (Mn), Zinc (Zn), Copper (Cu), Molybdenum (Mo) and Chlorine (Cl) are only needed in minute amounts but are crucial for a complete plant food diet. Exercise caution since an overabundance of these elements can cause problems.
The use of chemical symbols to identify the elements of a plant diet is a clue to understanding how plants like to absorb these nutrients – broken down as far as they can in single atoms and ions. Our job as gardeners is to make sure everything is there as a raw ingredient. The gardener isn’t the one to feed plants, our concern should be with the soil.
There is already a melting pot of what the plant needs coming from the rock base of the soil and the residual material from the demise of living creatures that existed in that space. In nature, plants will thrive in soil that suits them in a survival of the fittest approach. In our gardens however, we grow what we want to grow, not necessarily what would be happy growing there, so we have to feed the soil and engage the help of micro communities. Worms, decomposer beetles, bacteria, fungi and other soil dwelling creatures take dead material and break it down into a form our plants can use, helping move forward the wonderful cycle of life.
